Ford, The preferred method is to bring the feed impedance as close to 50 ohms as
possible and definitely lower the Q of the matching system. A multi wire cage
or a shunt of larger diameter such as .750 CATV hard-line, I think would improve
the feed efficiency and bandwidth. This is especially important for contests
when you are running back and forth between 1805 and 1850. A four wire cage
around the tower might have some other advantages as well as there may be a
slight pattern distortion with a wide spaced shunt similar to what happens with
a slant wire feed.
Herb (KV4FZ)
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